The present invention is intended to resolve the problem of the removal of chips in boring mills, in order to prevent the chips from remaining in the working region of the tool and causing problems concerning the quality of machining of the piece, the life of the tool and the automation of the working cycle of the boring mill.
The invention is intended to resolve this problem with the following idea for a solution. The chuck of the boring mill and the corresponding operating bar, together with the moving unit of the cylinder and piston assembly which provides the axial movement of the bar, are made with an axially hollow shape, so that they form a vertical duct which is open at the top next to the workpiece mounted in the chuck, and is open at the bottom above a conveyor with a filter and a unit for collecting and pumping the cutting fluid. The chips which are formed during the machining of the piece mounted in the chuck are transported and removed downwards, through the said duct, by at least one jet of fluid at high pressure, for example of the order of at least 130-200 bar, which has a location and direction such that it strikes the chip after its formation without interfering with the normal jet of fluid at low pressure which is applied uniformly to the tool. The jet or jets of fluid at high pressure which remove the chips consist of the same cutting fluid as that which is directed against the tool at low pressure. The chips and cutting fluid leaving the lower end of the said vertical duct are collected by the conveyor and filter assembly which removes the chips to a collection area and which filters and collects the fluid which is supplied by two different sets of pumps to the ducts formed in the toolholder and from which the jets at high and low pressure emerge for the various purposes mentioned above.